Diagnosing Crohn’s Disease

Do you think you or a loved one may have Crohn’s disease? While you may exhibit some of the symptoms of Crohn’s, it’s up to a gastroenterologist to determine whether you have the condition.

Dealing with any health problem can be emotionally and physically stressful, but the sooner Crohn's disease is diagnosed, the better chance you have to control its symptoms and minimize your discomfort. Crohn's disease is chronic, which means it can progress over time. Although there is no cure for Crohn's disease, effective treatments are available to help relieve the symptoms. An accurate professional diagnosis is the first step in your treatment for Crohn’s disease.

There are a number of diagnostic tests that can help your gastroenterologist determine whether you have Crohn’s disease. First, he or she will discuss your symptoms, talk about your medical history and then decide what types of tests may be necessary to diagnose Crohn’s disease.

It’s also important for the gastroenterologist to rule out other conditions since they may produce similar symptoms. Other conditions of the gastrointestinal tract, such as ulcerative colitis, may also cause abdominal cramping and diarrhea. However, conditions such as ulcerative colitis, inflammatory bowel disease, or “irritable bowel syndrome” are not the same as Crohn’s disease. Your gastroenterologist can make that determination by utilizing the appropriate diagnostic procedures.

Getting a physical

The first thing your gastroenterologist will do is perform a physical examination. This may include a closer look at two areas of your body. In the first area, the right lower quadrant of the abdomen, he or she will try to determine if there is any tenderness or any inflammatory masses present. The second area is called the anorectal area.

Your gastroenterologist will look in this area for any signs of hemorrhoids, anal fissures, perianal abscesses, or thick, mound-like, tender areas, and in women, signs of fistulas located between the vagina and the rectum. In addition, some people with Crohn's disease have a very constricted rectal opening that is so narrow that a physician is unable to insert a finger.

Blood and stool tests

Blood tests

A complete blood count test cannot provide a positive diagnosis of Crohn's disease. However it can reveal the following, which may be signs that Crohn’s disease is present:

• Anemia: May indicate that you are experiencing intestinal bleeding determined by the hemoglobin and hematocrit levels
• White blood cell levels: When elevated, may indicate Crohn's disease, an infection, or an inflammatory condition
• Differential: Shows the percentage of different kinds of white blood cells that comprise the total count and reveals the level of activity of inflammatory conditions or infection
• Platelet count: Determines the number of clotting cells (When the level is raised above normal it may indicate an infection or active inflammation.)
• Erythrocyte sedimentation rate (ESR): When elevated, may indicate inflammatory conditions or infection

A blood chemistry profile is a comprehensive test that is often ordered when Crohn's disease is suspected because it provides overall information about how well your body is functioning. This test reveals:

• Nutritional information
• State of general health
• Electrolyte levels
• Liver function
• Kidney function

Your physician may also order a Schilling test, which determines if your body absorbs vitamin B-12 the way it should. If you are deficient in vitamin B-12, you may become anemic.

Stool tests

Stool examinations are noninvasive tests that are performed to determine whether someone has Crohn's disease, ulcerative colitis, or a bacterial infection, which often have similar symptoms.

Usually, you can collect your own stool samples using a special vial provided by your physician, which you then mail to a lab. Your physician may also collect stool samples from you during an office visit for a rectal examination or a sigmoidoscopy.

Radiologic and Endoscopic Testing

Radiologic tests

Radiologic tests are often used to determine if someone has Crohn’s disease because they enable a physician to see inside the body. These tests can also help monitor your ongoing condition and response to treatment, as well as alerting your physician to any other health concerns.

There are a number of different radiologic tests. Several of these tests, such as the barium enema, upper GI, enteroclysis, and CT scan, involve the use of barium-based liquids. You should know that barium may cause constipation. Contact your physician if you experience problems from the tests.

Radiologic tests include:

• Barium enema: X-rays help your physician visualize the colon and the rectum. The terminal ileum, which is where the colon and the small bowel meet, usually can also be seen with this test. The test is very common and useful because it can help to diagnose Crohn's disease, monitor the progress of the disease, and uncover any complications that may exist, including strictures. It is also helpful in differentiating between Crohn's disease and ulcerative colitis.

• Upper gastrointestinal (GI) and small bowel follow-through: A barium-based drink is ingested and then X-rays that look at the esophagus, stomach, duodenum, and small intestine are used to determine the presence of ulcers and inflammation.

• Enteroclysis: A tube is inserted into the nose and guided through the stomach to the duodenum, which is where the small intestine begins. A barium-based fluid is infused through the tube and then X-rays reveal any abnormalities that may be inside of the small intestine, including lesions, obstructions, inflammation, or strictures.

• Computerized tomography (CT) scan: A very precise X-ray used to detect abnormalities in the liver, kidneys, and intestine. A dye is ingested or administered intravenously or inserted through the rectum. CT scans of the pelvis and the abdomen also enable physicians to guide needles and to insert catheters that drain abscesses.

• Ultrasound, also called sonography: By using sound waves, this test examines the organs of the pelvis and abdomen without any radiation exposure. Gallstones and abscesses, which may indicate a complication of Crohn's disease, can be detected with ultrasound. In addition, this test can also determine if the right kidney is swollen due to an obstruction of the right ureter by an inflamed ileum.

• Magnetic resonance imaging (MRI): By using radio waves and superconducting magnets that cause hydrogen molecules to vibrate within a person's body, the MRI, which does not use radiation exposure, can detect fistulas and abscesses that may be found in people with Crohn's disease.

Endoscopy

Endoscopic tests of the upper or lower GI tract can confirm Crohn's disease, locate areas of the intestine that are affected by the disease, and obtain tissue samples needed for biopsies and further examination. Endoscopes are thin, flexible, lighted tubes that are linked to a computer and a video monitor. An endoscopic examination is performed by inserting an endoscope into the rectum, mouth, or a small abdominal incision. This provides a physician with a very detailed view of the intestinal tract. If your physician suspects Crohn’s disease, he or she may recommend one of the following endoscopic procedures:

• Sigmoidoscopy: The most commonly performed endoscopic examination used to confirm a diagnosis of Crohn's disease. By using either a flexible or a rigid instrument, your physician can evaluate the rectum as well as the lower end of the colon for signs of inflammation. In patients with Crohn's disease, a sigmoidoscopy often reveals a colon wall marked by ulcerations, with areas of healthy tissue surrounding them. If needed, a biopsy can also be performed with a sigmoidoscopy.

• Colonoscopy: An examination of the full length of the colon as well as the lower part of the small intestine. In this procedure, the patient is sedated, and an endoscope is inserted into the rectum and guided through the entire colon. A colonoscopy can reveal if there is evidence of Crohn's disease in a particular section of the colon and the extent to which the area is inflamed. Additionally, compared to an X-ray, a colonoscopy can provide a much more detailed, inside view of the intestine. Colonoscopies are also used to rule out cancer concerns in patients who have had Crohn's disease for a long time.

• Upper endoscopy: An examination performed by placing an endoscope into the patient's mouth and guiding it through the stomach to the upper intestine. This procedure can detect ulceration and inflammation of all areas of the upper GI tract and may confirm a diagnosis of Crohn's disease.